To what extent has psychology revealed the nature of memory?

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Introduction

To what extent has psychology revealed the nature of memory? The extent that psychological research has revealed the nature of memory can be shown in through research and studies into different aspects of different types of memory. Research has mostly looked into the encoding, storage and duration of short-term and long-term memory. Jacobs (1887) did research into the capacity of short-term memory with the aim to investigate how much information can be held int he short-term memory. To do this, he devised a technique called the "serial digit span", which involved strings of digits which had to be recalled in the order in which they were given. He conducted a laboratory experiment in which participants were given these strings of number and asked to recall them in order, with the strings starting with 3 digits and increasing until the participant consistently failed to correctly reproduce the findings. He found that the average length of string remembered was between 5 and 9 items, with digits being recalled better than letters. Individual differences such as age affected the average amount of items correctly recalled, thus the conclusion that the short-term memory's capacity was 7�2 (between 5 and 9) digits. This research, however, found that other factors could affect the length of the string remembered, such as memory techniques like "chunking". ...read more.

Middle

Murdock (1962) tested the effects of primacy and recency in free-recall of a list of words, and found that the first and last words on a list of 20 words were remembered more than the words in the middle. He concluded that this is because the words at the start of a list can be rehearsed whilst the others are being read out, and the ones at the end can be remembered because they are fresh in the mind, and can be rehearsed after the word list has been read out, but the words in the middle are often forgotten because there is no chance of rehearsal for them. This supports the assumption that rehearsal increases the recall rate of words. As with the studies into capacity of the short-term memory, Peterson and Peterson (1959) and Murdock's (1962) studies into its duration were laboratory experiments which entailed tasks which were very unlikely to occur in day-to-day life, so they lack ecological validity. As a consequence, the results cannot be generalised, though the experiments do give us an insight into the duration of short-term memory. Another criticism is that Peterson and Peterson's (1959) study was carried out only on students, which is a biased sample resulting in lack of population validity. However, the research carried out by Peterson and Peterson (1959) ...read more.

Conclusion

Also, there are other types of encoding which were not tested in this experiment, such as visual encoding � for example, research by Brandimonte et al. (1992) supports the theory that some memories are encoded visually. This research consisted of participants being shown six-line drawings of familiar objects, and then they were asked to visualise the object and subtract a part of it and name the resulting image. Some were asked to do this whilst repeating a meaningless chant (disabling the use of acoustic encoding), and results from the investigation show that if acoustic encoding is prevented, visual encoding can be substituted in short-term memory. This contradicts Conrad's (1964) conclusion that encoding in short-term memory is all acoustic, instead suggesting that it is primarily acoustic, and other forms of encoding exist in the short-term memory. It can therefore be concluded that research into memory has revealed its nature to a considerable extent, but there is still a large amount left undiscovered. Many theories about different aspects of memory have gone a long way to help psychologists understand it and its processes, such as the encoding, capacity and duration of short-term memory. The capacity of long-term memory, for example, remains unknown as it is seemingly so vast, and many other features of both types of memory remain undiscovered. ...read more.

Related AS and A Level Cognitive Psychology essays

Procedures were as follows: participants were briefly shown a trigram and were asked to count backwards in threes from a specified number to stop them thinking about the letters. After intervals of 3,6,9,12,15 or 18 seconds, participants were asked to recall the original trigram and the procedure was then repeated several times with different trigrams.

The experimenter for each group would read them out. This list included words that sounded the same and has similar meanings. The 10 words were; log, fast, dog, sign, lip, teeth, last, hip, line, sweet. (See appendix 4). 20 consent forms were needed as participants had to give their consent before participating.

This shows that chunking does improve recall slightly but it is difficult to determine the true capacity of short-term memory. Limitations and modifications One limitation of the study was the participant sample used. Opportunity sampling from a sixth form target population was used and so the sample contained many biases like age and level of intelligence.

which included the idea that in order to recall information in the short term memory the information has to be first given attention in order to be passed on to short term. The recall result therefore depends on the amount of time rehearsed.

Discussion Validity Validity is if the measuring apparatus measures what it's meant to measure. By looking at the number of words remembered, it's an indicator of memory as it is clear that the more words you recall the more words were remembered, this is called face validity and its purpose

This was done by enticing the minority gender to partake in my experiment. However, this could have been a problem within itself in that these people may not have wanted to take part but I deliberately selected people who were interested. Results By analysing my raw data (see appendix 4)

from a disorganised, Null hypothesis * There will be no difference between the number of words recalled from the organised list compared with the disorganised list. Any difference will be due to chance. Method Design For this type of study into memory I will use an experimental method in the